Interchangeable tools and tool handles are known. Particular types of molded handles for tools having a core member are also known as typified by U.S. Pat. No. 3,770,033.
While the use of plastic materials to form handles for various types of tools such as garden tools has been suggested by the prior art, none has ever been produced nor made readily available except by the inventor himself. Such tools generally have wood handles that are circular in cross-section to fit into circular shanks and sleeves used as part of the well known tool structures. All wooden tool handles are easily shaped into a circular cross-section starting with an elongated wood blank having a rectangular cross-section
While it is known to use plastic as a substitute for wood in tool handles generally, the production of molded plastic handles for hand tools such as garden tools presents unique problems. The density of high impact, injection molded plastic is much greater than wood. Thus, weight considerations are very significant particularly because there is a certain flexibility, tensile strength and impact strength that must be maintained to achieve the desired results. The inventor himself has developed a significantly new gripping structure of a hand tool as set forth in his co-pending U.S. patent application Ser. No. 764,125 filed Aug. 9, 1985 now U.S. Pat. No. 4,639,029, with its written description being specifically incorporated by reference herein.
The known types of interchangeable hand tools generally have relatively complex and expensive coupling means for attaching the tool member to the tool end section of a handle. The particular prior art configuration provides no mechanism for adjusting the tightness of the fit between the removable tool structure with respect to the tool handle. Furthermore, the prior art structure used with known interchangeable tool handles can wear out rather quickly after use and provide a loose fit over the end of the tool handle. Such a loose fit increases the significance of the wear while the tool is in use.